1. Field of the Invention
The present invention is in the field of medical technology and concerns the storage organization of image data in a distributed system that comprises multiple clinical facilities that are engaged in data exchange with one another over a network.
2. Description of the Prior Art
Today clinical facilities normally have a number of departments, including satellites with a complete PACS (PACS=Picture Archiving and Communication System) with one or more modalities for the acquisition of medical image data or of other examination data (for example CT, MR, AX etc.), as well as with stores and databases, as well as management systems.
In such a distributed system (which can be a network of clinical facilities with multiple satellites that are distributed worldwide, for example), a very high data volume of medical image data is acquired, transferred and administered. High requirements for the storage organization with regard to storage space and access times result. With regard to the storage organization and data administration, it is also a significant requirement to enable an overview of all image data available in the distributed system from every satellite.
Moreover, a requirement exists in the medical field to ensure a high availability of the image data in the case of server, database or network failures.
The storage and archiving of examination data of a modality previously occurred only at specific databases within a satellite. In order to enable access spanning all satellites, it has been conventional to employ an administration and access layer at a higher abstraction level in the overall system. Which examination data are accessible and available at which satellites is administered in such an administration layer (which also includes databases). This has the disadvantage that a high administration expenditure is required in order to enable access over all satellites. A high level of availability can be realized only with difficulty.
A system known as the SIENET Magic Store System is commercially available from Siemens that has a Magic View component and a Magic Store component. The Magic Store component is always associated with one satellite and by default provides only information about data that are available at this satellite. The Magic Store component alone thus offers only a “local view” of the information or data. A “global view” is possible in this system only by the use of complicated ad hoc measures. All information with regard to examination data are stored and administered in two databases:
1. A patient directory (PDIR) contains all examination data sets for all patients (moreover, additional details with regard to a patient are stored here, for example patient name, birth date, gender, hospital department, patient identification number etc.)
2. An image management system database (IMS) is designed to stored image data with regard to the examinations. For example, this contains images of patients that are currently examined or that have been examined recently. In both databases (IMS, PDIR), searches have previously been conducted via queries in the event that workstations request specific data sets of specific patients.
The previous systems do not provide a satisfactory result (in particular due to the default limitation to the “local view”) in satellite-encompassing accesses to examination data that are stored or, respectively, saved at different locations in a distributed system and which sometimes must also be accessed very quickly (in particular in the scope of a diagnosis or finding). The results also are not satisfactory with regard to a high degree of availability of the image data and the provision of an overview of all available image data in the distributed system, or such results could be achieved only with a high expenditure and high network utilization.